The question everyone asks in week two. The honest answer has two halves, and the second one is the awkward bit.
First, how hair actually grows
Scalp hair grows in a cycle, and at any moment your hairs are at different points in it.
Most — roughly 85 to 90% — are in the growing phase, which lasts somewhere between two and six years. A small proportion are in a brief transition phase of a couple of weeks. The rest, around 10 to 15%, are in a resting phase that lasts about three months, at the end of which the hair sheds and a new one begins growing in its place.
Two things follow from that.
The first is that hair grows slowly. The commonly cited average is around a centimetre a month, though it varies considerably between people. Whatever is happening nutritionally, you are not going to see it quickly, because there is nothing to see quickly.
The second is that the hair emerging from your scalp this month started forming a while ago. Anything you change today shows up in what grows afterwards — not in the length already on your head.
This is why a fortnight is not a meaningful test of anything, and why any product promising visible change in two weeks is making a promise the biology doesn't support.
What we can and can't tell you
We're not going to give you a number of weeks, because we're not permitted to and because it wouldn't be true.
What we can tell you is what the nutrients do. Biotin, zinc and selenium each contribute to the maintenance of normal hair — that's the authorised wording, assessed and accepted by regulators. Like any nutrient, they work through consistent intake rather than a single dose, in the same way that eating one orange doesn't top up your vitamin C for the month.
Anyone who gives you a specific timeframe attached to a specific outcome is making a claim no hair supplement in the UK is authorised to make.
Now the awkward half
Here's the thing that gets left out of every article on this subject.
The question isn't really “how long does it take.” It's “how long will you keep going.” And for most people taking most supplements, the honest answer is: not very.
The pattern is familiar enough to be a cliché. You buy the pot with genuine intent. You're perfect for ten days. Then there's a morning you're rushing, and you skip it. Skipping is easier the second time. By week five you're taking it three days out of seven, and by week eight the pot has migrated behind the coffee jar, where it will sit until you throw it out.
Nobody decides to stop. It just erodes.
And because nutrients need consistency, the person who takes a supplement four days a week for two months hasn't run a shorter version of the experiment. They've run no experiment at all — and then concluded the product doesn't work.
What actually helps you keep going
The behavioural research on habits is unglamorous but consistent, and it says roughly three things.
Attach it to something you already do. New habits stick far better when they piggyback on an existing one. “Take a supplement” is a new behaviour you must remember. “Have it with my morning drink” is an existing behaviour with something added.
Make it something you want, not something you tolerate. Anything faintly unpleasant needs willpower every single time, and willpower is exactly what runs out on a Tuesday in February.
Keep it visible. The reason the pot ends up behind the coffee jar is that once it's out of sight it stops existing.
Which is why ours is a hot chocolate
We'll be straightforward about our interest here: this is what Cocoa Locks is built on.
It isn't a tablet, it's a drink — two teaspoons in a mug, hot water, thirty seconds, 26 calories. Not because a drink is nutritionally superior to a capsule; it isn't. But because a hot chocolate attaches itself to a routine you already have, and it's something most people look forward to rather than endure.
That's a claim about behaviour, not about hair. It's the only advantage we'd claim, and we think it's the one that actually decides whether a supplement does anything for you.
“I hate swallowing pills and this is tasty… something I look forward to drinking every day.”
So, how long?
Longer than you want. Long enough that the honest advice is to stop checking the mirror and start thinking about whether you've built something you'll still be doing at Christmas.
If you have — whatever product you choose — you'll get a real answer. If you haven't, you'll get the same non-answer most people get, and you'll blame the formula.
More on why we made it a drink · What's in it, in full
Food supplements should not be used as a substitute for a varied and balanced diet and a healthy lifestyle. If you're experiencing sudden, patchy or significant hair loss, speak to your GP — it can have medical causes that are worth investigating properly.